diff --git a/src/ol/Geolocation.js b/src/ol/Geolocation.js
index b281d6f0b7..9e771de3e9 100644
--- a/src/ol/Geolocation.js
+++ b/src/ol/Geolocation.js
@@ -98,7 +98,7 @@ class Geolocation extends BaseObject {
     /**
      * The unprojected (EPSG:4326) device position.
      * @private
-     * @type {import("./coordinate.js").Coordinate}
+     * @type {?import("./coordinate.js").Coordinate}
      */
     this.position_ = null;
 
diff --git a/src/ol/Image.js b/src/ol/Image.js
index f9d39dc8b3..a7f0797b0e 100644
--- a/src/ol/Image.js
+++ b/src/ol/Image.js
@@ -59,7 +59,7 @@ class ImageWrapper extends ImageBase {
 
     /**
      * @private
-     * @type {function():void}
+     * @type {?function():void}
      */
     this.unlisten_ = null;
 
diff --git a/src/ol/ImageTile.js b/src/ol/ImageTile.js
index 8d934f7c39..64b90fa22a 100644
--- a/src/ol/ImageTile.js
+++ b/src/ol/ImageTile.js
@@ -46,7 +46,7 @@ class ImageTile extends Tile {
 
     /**
      * @private
-     * @type {function():void}
+     * @type {?function():void}
      */
     this.unlisten_ = null;
 
diff --git a/src/ol/MapBrowserEvent.js b/src/ol/MapBrowserEvent.js
index 956c639f24..dc301946b7 100644
--- a/src/ol/MapBrowserEvent.js
+++ b/src/ol/MapBrowserEvent.js
@@ -31,13 +31,13 @@ class MapBrowserEvent extends MapEvent {
 
     /**
      * The map pixel relative to the viewport corresponding to the original browser event.
-     * @type {import("./pixel.js").Pixel}
+     * @type {?import("./pixel.js").Pixel}
      */
     this.pixel_ = null;
 
     /**
      * The coordinate in the user projection corresponding to the original browser event.
-     * @type {import("./coordinate.js").Coordinate}
+     * @type {?import("./coordinate.js").Coordinate}
      */
     this.coordinate_ = null;
 
diff --git a/src/ol/PluggableMap.js b/src/ol/PluggableMap.js
index a65da29671..a82fec0687 100644
--- a/src/ol/PluggableMap.js
+++ b/src/ol/PluggableMap.js
@@ -232,7 +232,7 @@ class PluggableMap extends BaseObject {
 
     /**
      * @private
-     * @type {Array<import("./events.js").EventsKey>}
+     * @type {?Array<import("./events.js").EventsKey>}
      */
     this.layerGroupPropertyListenerKeys_ = null;
 
@@ -292,7 +292,7 @@ class PluggableMap extends BaseObject {
 
     /**
      * @private
-     * @type {Array<import("./events.js").EventsKey>}
+     * @type {?Array<import("./events.js").EventsKey>}
      */
     this.keyHandlerKeys_ = null;
 
diff --git a/src/ol/control/MousePosition.js b/src/ol/control/MousePosition.js
index 3d97fe04d1..cb96bf3514 100644
--- a/src/ol/control/MousePosition.js
+++ b/src/ol/control/MousePosition.js
@@ -97,7 +97,7 @@ class MousePosition extends Control {
 
     /**
      * @private
-     * @type {import("../proj/Projection.js").default}
+     * @type {?import("../proj/Projection.js").default}
      */
     this.mapProjection_ = null;
 
diff --git a/src/ol/control/ZoomToExtent.js b/src/ol/control/ZoomToExtent.js
index 32f59de1a9..6c3142a6c0 100644
--- a/src/ol/control/ZoomToExtent.js
+++ b/src/ol/control/ZoomToExtent.js
@@ -41,7 +41,7 @@ class ZoomToExtent extends Control {
     });
 
     /**
-     * @type {import("../extent.js").Extent}
+     * @type {?import("../extent.js").Extent}
      * @protected
      */
     this.extent = options.extent ? options.extent : null;
diff --git a/src/ol/format/TopoJSON.js b/src/ol/format/TopoJSON.js
index 10f00ab865..c8cc330cf7 100644
--- a/src/ol/format/TopoJSON.js
+++ b/src/ol/format/TopoJSON.js
@@ -73,7 +73,7 @@ class TopoJSON extends JSONFeature {
 
     /**
      * @private
-     * @type {Array<string>}
+     * @type {?Array<string>}
      */
     this.layers_ = options.layers ? options.layers : null;
 
diff --git a/src/ol/interaction/DragAndDrop.js b/src/ol/interaction/DragAndDrop.js
index f4921ba2b3..5cb69e3b08 100644
--- a/src/ol/interaction/DragAndDrop.js
+++ b/src/ol/interaction/DragAndDrop.js
@@ -115,7 +115,7 @@ class DragAndDrop extends Interaction {
 
     /**
      * @private
-     * @type {Array<import("../events.js").EventsKey>}
+     * @type {?Array<import("../events.js").EventsKey>}
      */
     this.dropListenKeys_ = null;
 
diff --git a/src/ol/reproj/Tile.js b/src/ol/reproj/Tile.js
index e2afe70093..909b125e7e 100644
--- a/src/ol/reproj/Tile.js
+++ b/src/ol/reproj/Tile.js
@@ -104,7 +104,7 @@ class ReprojTile extends Tile {
 
     /**
      * @private
-     * @type {Array<import("../events.js").EventsKey>}
+     * @type {?Array<import("../events.js").EventsKey>}
      */
     this.sourcesListenerKeys_ = null;
 
diff --git a/src/ol/style/IconImage.js b/src/ol/style/IconImage.js
index 940b946f83..d2361e5bb7 100644
--- a/src/ol/style/IconImage.js
+++ b/src/ol/style/IconImage.js
@@ -53,7 +53,7 @@ class IconImage extends EventTarget {
 
     /**
      * @private
-     * @type {function():void}
+     * @type {?function():void}
      */
     this.unlisten_ = null;